Cardiac Anatomy - Hoagland Flashcards
What causes cardiac tamponade? What are the symptoms?
Cardiac tamponade is caused by effusion into the pericardial sac.
- Venous Hypertension
- Pulmonary Artery Hypertension
- Tachypnea
- Tachycardia
- Narrowing of BP
What causes the venous hypertension in cardiac tamponade?
Increased pressure in the pericardial sac restricts the expansion of the ventricle and decreases output. This leads to a back-up in the venous system and hypertension.
What causes the pulmonary artery hypertension in cardiac tamponade?
Increased pressure in the pericardial sac restricts the expansion of the ventricle and decreases output. This leads to a back-up in the pulmonary artery and hypertension.
What causes the tachypnea in cardiac tamponade?
The pulmonary hypertension causes pleural effusion, which decreases available oxygen exchange area, requiring increased breathing.
What causes the tachycardia in cardiac tamponade?
The increased pericardial pressure decreases cardiac output. Because metabolic requirements are static, heart rate must increase.
What causes the blood pressure narrowing in cardiac tamponade?
The increased pericardial sac pressure decreases left ventricle output. This drops the systemic blood pressure and leads to narrowing of the blood pressure.
Where would you auscultate the aortic valve?
Immediately to the right of the sternum, in the second intercostal space.
Where would you auscultate the pulmonary valve?
Immediately the to left of the sternum, in the second intercostal space.
Where would you auscultate the tricuspid valve?
Immediately to the left of the sternum, in the fifth intercostal space.
Where would you auscultate the mitral valve?
In the fifth intercostal space, on the mid-clavicular line.
Where on an x-ray would you see the aortic knob?
To the (patient’s) left of midline, right below the clavicle.
What structures are most likely to be injured from a ventral penetrating injury?
The right ventricle or atrium, depending on whether the penetration happened right (atrium) or left (ventricle) of the sternum.
How would you most likely injure the left ventricle or left atrium?
A dorsally or laterally penetration injury
What borders the heart?
Laterally -lungs and the phrenic nerve
Anterior- sternum, ribs
Posterior- trachea superiorly, esophagus
Inferiorly-Diaphragm
What arteries branch off of the aorta?
Right brachiocephalic
Left common carotid
left subclavian
What arteries branch off of the right brachiocephalic?
Right subclavian
Right common carotid
What nine places can be used to take a pulse?
Superficial Temporal (temple) Facial (lateral jawline) Carotid (neck) Subclavian (above clavicle) Brachial (upper arm) Radial (wrist) Femoral (medial inguinal crease) Popliteal (back of knee) Dorsalis Pedis (between first and second metatarsal)
What are the three layers of the pericardium?
Moving superficially:
visceral serous pericardium
parietal serous pericardium
fibrous pericardium
Where is the pericardial cavity?
Between the visceral serous pericardium and the parietal serous pericardium
What is the transverse cavity?
The space dorsal to the aortic and pulmonary arteries and ventral to the superior vena cava.
What is the oblique cavity?
The space bordered by the inferior vena cava and the right pulmonary veins of the right and by the left pulmonary veins on the left.
Where do the coronary arteries branch off?
The aortic artery
This is a good way to get your bearings when looking at a heart
What branches off of the right coronary artery? The left coronary artery?
Right Coronary Artery:
Sinuatrial branch
Right marginal branch
Posterior interventricular
Left Coronary Artery:
Circumflex branch
Left anterior descending branch/anterior interventricular branch
Left marginal branch
What veins and arteries of the heart are paired together?
Great cardiac vein: Anterior interventricular artery
Middle cardiac vein: Posterior interventricular artery
Small cardiac vein: Right marginal branch
What is the fossa ovale? Why do we have it?
The fossa ovale is a thin wall between the left and right atrium. During fetal development, the fossa ovale opens between the atrium to protect the lungs.
What condition can you see with a patent fossa ovale?
Paradoxical embolism
What is the significance of the right auricle?
The right auricle is a weaker point of the heart with a lot of hemostasis. Clots can frequently form here.
What are the important components of a valve? What do they do?
Leaflets-form the actual flaps of the valve
Cordae tendinaea- high tension cords that connect the papillary muscles to the valve
Papillary muscles- prevent prolapse or inversion of valve
When are all valves closed?
At the beginning of diastole
What valves are open during diastole? What valves are closed?
Mitral and Triscuspid valves are open
Pulmonary and Aortic valves are closed.
What valves are open during systole? What valves are closed?
Pulmonary and Aortic valves are open
Mitral and Tricuspid valves are closed?
What do the following valves connect? Aortic Pulmonary Tricuspid Mitral
Aortic opens into aorta from the left ventricle
Pulmonary opens into the pulmonary veins from the right ventricle
Tricuspid connects the right atrium and the right ventricle
Mitral connects the left atrium and the left ventricle
(Wigger’s Diagram) What causes the atrioventricular valves to close?
When rising ventricular pressure, due to isovolumetric contraction, exceeds atrial pressure.
1) What type of valve are the mitral and tricuspid valves called?
2) What type of valve are the aortic and pulmonary valves called?
1) Mitral and tricuspid: Atrioventricular
2) Aortic and pulmonary: Semilunar
What does the P wave of an electrocardiogram represent?
Atrial Depolarization
What does the QRS complex of an electrocardiogram represent?
Ventricular Depolarization
What does the T wave of an electrocardiogram represent?
Ventricular Repolarization
What heart event is not seen on a normal electrocardiogram? Why not?
Atrial Repolarization. It is masked by the larger QRS complex.
(Wigger’s Diagram) What causes the aortic valve to open?
The aortic valve opens when ventricular pressure exceeds aortic pressure.
(Wigger’s Diagram) When auscultating the heart, what produces S1? When does this occur in the heart’s cycle?
S1 results from the closure of the atrioventricular valves. This occurs at the start of systole.
(Wigger’s Diagram) When auscultating the heart, what produces S2? When does this occur in the heart’s cycle?
S2 results from closure of the semilunar valves. This occurs at the start of diastole.
After the aortic valve closes, there is a small, short rise in aortic pressure. What is this called? Why does it occur?
This is called the dicrotic wave. It occurs due to elastic recoil in the aorta following closure of the aortic valve.
Note: the dicrotic NOTCH is technically the small DIP in aortic pressure that occurs immediately with aortic valve closure, before the recoil causes the dicrotic wave.
Where is the cardiac plexus located?
Near the tracheal bifurcation & the ligamentum arteriosum.
Where do postganglionic sympathetic fibers to the heart arise from? Where do their respective preganglionic fibers arise from?
Postganglionic fibers: from the upper sympathetic chain ganglia.
Preganglionic fibers: 3 cervical levels and T1-T5.
At what levels do afferent fibers from the heart enter the spinal cord? When the heart is in pain, what important clinical finding arises from this fact?
T1-T5.
Referred pain in the region of the left shoulder.
Hypertrophy of which chamber of the heart could lead to obstruction of the esophagus?
Left atrium - it is closest to the esophagus.
Where in the vascular system is the line used in coronary angioplasty typically inserted into?
The femoral artery.
What is important to remember when inserting an autologous vein graft for a coronary bypass surgery?
Veins have valves! Orient the vein so the valves will be open in the direction of arterial blood flow!
Which vessel is the most frequent site of coronary artery occlusion?
Left Anterior Descending (LAD) artery / Anterior interventricular branch (of left coronary artery)
What artery is the vessel of choice in coronary artery bypass grafting (CABG)?
(Left or Right) Internal Thoracic Artery (previously internal mammary artery)
What are some common contributing factors of heart failure?
- Myocardial Infarction
- Toxins (e.g. alcohol)
- Hypertension
- Myocarditis
- Idiopathic / Genetic
What are some risk factors of coronary atherosclerosis? What is a major problem associated with this condition?
Risk Factors:
- Hyperlipidemia
- Hypertension
- Diabetes
- Smoking
- Aging
Problem:
Myocardial Infarction!
What pathologic changes to the myocardium might you find in a heart with systolic dysfunction? In what conditions would you see this?
Weak, atrophied, or dead myocardium resulting in a heart not strong enough to pump blood at a sufficient pressure
Conditions: Primary dilated cardiomyopathy (CMP), Myocarditis
What pathologic changes to the myocardium might you find in a heart with diastolic dysfunction?
Hypertrophied heart muscle that lacks the space to sufficiently fill with blood between contractions
Conditions: Hypertrophic cardiomyopathy (CMP), Restrictive CMP, Aging
What clinical symptoms might you find secondary to systolic dysfunction?
Signs of inadequate cardiac output:
- Fatigue
- Cool extremities
- Mental obtundation (dullness)
- Organ dysfunction (esp. kidneys, liver)
What clinical symptoms might you find secondary to LEFT-sided diastolic dysfunction?
Signs of tissue congestion and left ventricular failure:
- Dyspnea
- Orthopnea (Dyspnea when lying flat)
- NO elevation of venous pressure
What clinical symptoms might you find secondary to RIGHT-sided diastolic dysfunction?
Signs of tissue congestion and right heart failure:
- Cyanosis
- Jugular vein engorgement
- Liver enlargement
- Ascites
- Leg edema
- ELEVATED venous pressure
